[PATCH] ASoC: rockchip-max98090: Fix NULL pointer dereference while accessing to jack.

From: Enric Balletbo i Serra
Date: Mon May 09 2016 - 06:46:31 EST


Commit f2ed6b07645e ("ASoC: Make aux_dev more like a generic
component") caused a regression on this driver, since now a
kernel oops is seen when rockchip-mac98090 driver is loaded.

That commit changed the probing of aux_devs before checking
new DAI links, so for this driver rk_98090_headset_init is
called before rk_init and then the kernel oops due a NULL
pointer dereference inside rk_98090_headset_init function
since there is a call that tries to access the jack pointer
which has not been allocated yet.

This is the call chain that causes the crash:

rk_98090_headset_init
-> ts3a227e_enable_jack_detect
-> snd_jack_set_key
rk_init
-> snd_soc_card_jack_new

This patch moves the new jack object creation from rk_init
to rk_98090_headset_init function making sure the jack is
created before is accessed.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
sound/soc/rockchip/rockchip_max98090.c | 50 ++++++++++++++++++----------------
1 file changed, 27 insertions(+), 23 deletions(-)

diff --git a/sound/soc/rockchip/rockchip_max98090.c b/sound/soc/rockchip/rockchip_max98090.c
index 543610282cdb..abb64a553967 100644
--- a/sound/soc/rockchip/rockchip_max98090.c
+++ b/sound/soc/rockchip/rockchip_max98090.c
@@ -114,43 +114,27 @@ static int rk_aif1_hw_params(struct snd_pcm_substream *substream,
return ret;
}

-static int rk_init(struct snd_soc_pcm_runtime *runtime)
-{
- /* Enable Headset and 4 Buttons Jack detection */
- return snd_soc_card_jack_new(runtime->card, "Headset Jack",
- SND_JACK_HEADSET |
- SND_JACK_BTN_0 | SND_JACK_BTN_1 |
- SND_JACK_BTN_2 | SND_JACK_BTN_3,
- &headset_jack,
- headset_jack_pins,
- ARRAY_SIZE(headset_jack_pins));
-}
-
-static int rk_98090_headset_init(struct snd_soc_component *component)
-{
- return ts3a227e_enable_jack_detect(component, &headset_jack);
-}
-
static struct snd_soc_ops rk_aif1_ops = {
.hw_params = rk_aif1_hw_params,
};

-static struct snd_soc_aux_dev rk_98090_headset_dev = {
- .name = "Headset Chip",
- .init = rk_98090_headset_init,
-};
-
static struct snd_soc_dai_link rk_dailink = {
.name = "max98090",
.stream_name = "Audio",
.codec_dai_name = "HiFi",
- .init = rk_init,
.ops = &rk_aif1_ops,
/* set max98090 as slave */
.dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF |
SND_SOC_DAIFMT_CBS_CFS,
};

+static int rk_98090_headset_init(struct snd_soc_component *component);
+
+static struct snd_soc_aux_dev rk_98090_headset_dev = {
+ .name = "Headset Chip",
+ .init = rk_98090_headset_init,
+};
+
static struct snd_soc_card snd_soc_card_rk = {
.name = "ROCKCHIP-I2S",
.owner = THIS_MODULE,
@@ -166,6 +150,26 @@ static struct snd_soc_card snd_soc_card_rk = {
.num_controls = ARRAY_SIZE(rk_mc_controls),
};

+static int rk_98090_headset_init(struct snd_soc_component *component)
+{
+ int ret;
+
+ /* Enable Headset and 4 Buttons Jack detection */
+ ret = snd_soc_card_jack_new(&snd_soc_card_rk, "Headset Jack",
+ SND_JACK_HEADSET |
+ SND_JACK_BTN_0 | SND_JACK_BTN_1 |
+ SND_JACK_BTN_2 | SND_JACK_BTN_3,
+ &headset_jack,
+ headset_jack_pins,
+ ARRAY_SIZE(headset_jack_pins));
+ if (ret)
+ return ret;
+
+ ret = ts3a227e_enable_jack_detect(component, &headset_jack);
+
+ return ret;
+}
+
static int snd_rk_mc_probe(struct platform_device *pdev)
{
int ret = 0;
--
2.8.1